Power operated ratchet wrench



June 2l, 1955 A. J. BRAME 2,711,111

n POWER OPERATED RATCHET WRENCH` v Filed July 29, 1955 n 2 swaps-sheet 1l n i; vg i510 June 2l, 1955 A.`J. BRAME v POWER OPERATEID RATCHETWRENCH Filed July 29, 1953 ALLE/v J. .9m/we,

INVENToR A T TORNK u @Patented .irme 21, 1955 2,711,111 POWER OPERATEDRATCHET WRENCH Allen James Brame, Los Angeles, Calif., assignor toTubing Appliance Company, Inc., Los Angeles, Calif., a corporationApplication July 29, 1953, Serial No. 371,063

19 Claims. (Cl. 81 58.2)

This invention relates to power operated wrenches and more particularlyto a power operated wrench of the split socket type such as shown in myco-pending application, Ser. No. 313,728.

Power operated wrenches of different types have been heretoforeproposed, but have not been universally adopted for several reasons.Such wrenches as have been actuating the member engageable with theelement to be turned has not been positive in action or broke down underhigh stresses to which this type of tool is often subjected. n

The power wrench of the present invention, in the broadest aspectsthereof, comprises a universally adjustable wrench having a head memberof small compass, but yet of high strength to provide a socket retainingmember which is light in weight but yet capable of withstanding theunusually high stresses to which, as above mentioned, this type of toolis often subjected. The socket'retaining member is rotatably driven by aratchet and pawl drive means which coacts with the head member to mountand support the socket retaining member, as well as to reinforce thesame in all positions thereof during use of the wrench. A

The ratchet and pawl drive means of the wrench of the present inventionis one which will take relatively high loadings and the load capacity isnot limited to the shear strength of the means used to pivotally mountthe pawls. The drive means is such that a high force positive drive isconverted into a relatively high torque couple in the socket retainingmember.

The pawl and ratchet drive means is actuated from an external powersource of any conventional type capable of producing a rotary forcewhich serves through a transmission means to operate in timed relationthe pawl and ratchet drive for the socket retaining member. The drivemeans is not only positive in action, but is capable of converting thepositive drive into a relatively high torque couple throughout a longservice life.

To insure the positive drive, the transmission means is such as toactuate the drive in the alternate directions necessary to produce therequired torque couple in the socket retaining member. In other words,no resilient return means, which might fail or deteriorate in use, areused to actuate the drive. Thus the service life of the wrench of thepresent invention is prolonged and with little or no maintenanceexpenditures under normal uses.

In one embodiment of the ratchet drive, a pair of pawls are pivotallysecured to a carrier member which coacts with the head to mount andsupport the socket retaining member and to reinforce this member in allrotative positions of adjustment thereof. The carrier is arcuately movedto bring about the desired timed relation of the drive through aneccentric cam element engageable with follower means forming a part ofthe pawl carrier. This cam element is driven from a rotary shaft andthrough 'ie follower meansy of the carrier arcuately moves the latter inthe alternate directions necessary to produce the torque Vcouple in thesocket mounting member.

VIn another embodiment of the wrench herein 1llus trated, the carriermember of the transmission means is actuated to produce the positivedrive by a mechanism amplifying the output of the power source. Thisamplifying mechanism includes la lever means provided with a cam elementengageable with the carrier to arcuately move the latter in thealternate directions necessary to produce the torque couple in thesocket mounting member. The amplifying mechanism of the transmissionmeans in no way complicates the operative elements of the wrench and allstresses created by this mechanism are taken by the body element of thewrench.

The external power means used to actuate the wrench forms no part of thepresent invention and may be any conventional power source desired. Inthe illustrated embodiments of the wrench herein shown this power sourceis'preferably one which will rotatably drive a shaft which forms a partof the transmission means for actuating the pawl and ratchet drive. Y

Other features and advantages of the present invention will behereinafter apparent from the following description, particularly whentaken in connection with the accompanying drawing, in which Figure l isa View partly in section and partly in elevation of one embodiment ofthe wrench of the present invention;

Figure 2 s a section takenV along line 2 2 of Figure l;

Figure 3 is a section taken along line 3 3 of Figure 2;

Figure 4 is a top plan view of a modified form of the wrench of thepresent invention;

Figure 5 is a View partly in elevation and partly in section of theembodiment of the wrench shown in Figure 5; and

Figure 6is a section taken along line 6 6 of Figure 5.

The wrench of the present invention, and more particularly theembodiment of Figures l through 3, cornprises a head element 1i?generally oval in cross sectional shape and a support element 11 yformounting a handle, a portion of which is shown at 11a. The supportelement 11 preferably is formed integral with. a body member 12 forminga part of the head element 1i), although, if desired, this element canbe formed separate from the body member 12 and assembled therewith.

The body member 12, in the illustrated embodiment of this form of thewrench of the present invention, is formed as a casting presenting aconcavity'l for receiving the operative members of the wrench. A slot 14opens into the concavity at the one end of the body member, as bestvseen in Figure l, and the inner end of the slot is enlarged to form acircular opening or bore 15 extending through thev body member 12. Thewall 16 of the body member12 is formed with an arcuate flange 17inwardly extending and concentric with the bore 15. This ilange, asshown in Figure 2, coacts throughout the extent thereof with the wall 18of the body member 12 to form an annular groove 19 concentric with theange 17 and consequently the bore 15 of the body member 12.

Rotatably mounted within the bore 15 is a hub or ratchet member 21formed with a slot 22 of a width substantially equal to the width of theslot 14 and communicating with `.a `longitudinally extending borepresenting an arcuate internal wall surface 23. The hub or ratchetmember 21 forms a socket member retaining means for the surface 23thereof is adapted to engage the complementary surface of a shank 24 ofa selected socket member 25'. The surface 23 terminates at the oppositeedges of the slot 22 in driving elements 26, each formed with a radiallyextending driving face adapted to facewisely engage a complementary faceof the Shank 24 of the socket member mounted to the wrench. As shouldnow be seen, rotation of the hub 21 through the inter-engagement of thefaces of the driving elements 26 and the shank 24 will rotatably drivethe socket member 25.

The hub or ratchet member 21 is formed, as best seen in Figure 2, withan annular shoulder or ange 27 complementary to the groove 19 of thebody member. The hub is also provided with an annular groove 28 whichreceives the flange 17 of the wall 16 of the body member. It will thusbe seen that the inter-nested flange and groove assembly just describedmounts and supports the hub 21 for rotative movement about an axiscoincident with the longitudinal axis of the bore 15. The inten engagingwalls of the flanges and grooves not only guide the hub during thisrotative movement, but, as will be hereinafter more fully explained,also reinforces the hub against stresses encountered in the use of thewrench.

The flange 27 of the hub 21 is provided with fullV width notch-likegrooves 29 and teeth 31 circumferentially spaced about theV entireunslotted periphery of the flange 27. The grooves 29 and teeth 31 extendin a direction parallel to the longitudinal axis of the bore and form apart of the transmission means of the wrench of the present invention.The teeth 31 are engaged by a plurality of pawls, at least a pair ofwhich are indicated by the reference character 32. The pawls 32 areformed with terminal portions 33, generally cylindrical in shape, eachreceived within bores formed in a carrier 34 mounted within theconcavity 13 for arcuate movement aboutan axis coincident with thelongitudinal axis of the bore 15. n

The pawls 32 are normally urged into engagement with the teeth 31 bycoil springs 35 received within small recesses 36 formed in the carrier34 adjacent the bores receiving the terminal portions 33 of the pawls.It will be seen that the orientation of the pawls 32 is such thatrotation of the hub is permitted in only one direction. In order toreverse the direction of effective rotation of the hub and, therefore,of the socket member 25, it is necessary, as will be later understood,to merely reverse the relative position of the socket mounted to the hub21.

The carrier 34 is vformed with a slot 37 of a width substantially equalto the width of the slot 14 and this slot is enlarged at the inner endthereof to form a circular opening dened by an arcuate flange 38 whichis slidhub member 21 and thus coacts with the anges 17 and 5.

26 to reinforce the hub 21 in all rotative positions of adjustmentthereof.

The carrier 34 is also formed with a large arcuate flange 41 dependingfrom the portion thereof opposite to the slot 37, the one edge face ofwhich bears against and engages the inner surface of the wall 16 of thebody member 12. This flange acts to properly space the carrier 34 withinthe concavity 13 and positions thecarrier 20 as to insure the desiredcoaction with the hub 21.

lt should now be seen that by arcuately moving the carrier 34 inalternate directions, the pawls 32 will rotatively drive the hub 21 andconsequently the socket member 25 mounted thereto. In the illustratedembodiment of the wrench now being described, this alternate movement ofthe carrier 34 is effected through an eccentric cam 42 carried at theone end of a rotary shaft 43 coaxially mounted within the handle element11 by suitable bearing members 44. Fixed to the inner end Y when theshank 24 is properly mounted 4 tion of the shaft 43. hardened rod-likeelementV presenting an external cylindrical surface 47, is formed with ablind bore 48 slidably receiving the pin 46. Thus the pin 46 mounts thecam 42 to the shaft 43 for movement in a circular path aboutA a centerfixed by the shaft 43. The cam 42 is operatively connected to thecarrier 34 by its reception in a follower member 49 comprising a bearingelement presenting an external cylindrical wall surface partiallyembracing the cam 42.

The follower member 49 has a longitudinal extent greater than the lengthof the cam 42 and is formed with a slot passing the pin 46. As the shaft43 is rotatably driven to move the pin 46 in its circular pathconcentric with the shaft 43, the cam 42 reciprocally moves within thefollower member and also moves arcuatelyV about an axis coincident withthe longitudinal axis of the Vfollower member. ment of the cam produces,as should now be seen,

arcuate movement of the carrier 34 in alternate direc-V tions to bringabout the intermittent drive action of the, Y

pawls 32 engaged with the teeth 31 of the hub 21.

The transmission means formed byk the cam 42 and i its operativeconnection with the follower member 49l positively moves the carrier 34intermittently about a center coincident with the axis of the bore 15.The drive of the carrier is, therefore, positive in actionV and does notdepend upon any resilient elements for effecting return movement of thecarrier after it has beenV moved to one of its alternate positions bythe cam. The operative connection between the carrier and the cam,because of the large surface contact engaged, gives a long service lifeand does ynot present any high pressure areas subject to extensive wear.

To hold'the hub 21 against inadvertent return movement by the frictionaldrag of the :pawls 32, as they freely ratchet over the teeth 31, apairof holding pawls 52 are pivotally mounted to the body member 12 and"these pawls are normally engaged with theV teeth Y31y under the urgingof the springs 53 seated within Vthe, j *y recess 54 formed in the bodymember 12. The pawls 52 will act to hold the hub against rotativemovement f in a direction opposite to the drive movement produced by thepawls 32 as the carrier 34 is moved through the v i action of the cam42. The pawls 52, as Should now be appreciated, are merely holding pawlsand will freely Y ratchet as the hub is driven by the pawls .32, yet areeffec-` tive to hold the` hub against movement as the carrier moves thepawls 32 in their inoperative cycle fof the drive.

As above explained the pawls 32 areV so oriented las Y i To hold theshank 24 in either of the two positions`v on the h-ub 21 somefriction'detent means, such asY vthe spring pressed ball detent 55, maybe employed.v To increase the holding action of the detent a groove 56'may be formed about the shank 24 forreceiving the ball in either ofthe'two positions on the hub 21.

The operative parts of the wrench are heldin the concavity 13 by a faceplate 57 mounted to the body member by mounting screws 58 passed throughopenings in the plate 57 and threadedly engaged in tapped bores 59formed in the thickened wall portion of the body member 12. Thisthickened wall portion is formed with a shoulder 61 which extendsforwardly to the slot 1d and forms a face against which the cover plate5.7 is clamped as the screws 58 are tightened. The cover plate The cam42, here shown as a Y This compound movethe hub from thatAillus-jz y 57is formed, as shown, with a circular opening for passing the one end ofthe hub member 21 and this opening communicates with a slot which asshown in Figure 1 registers with the slots formed in the hub and bodymember.

The plate 57 acts merely as a cover element and carries little, if any,stress during the use of the wrench. Actually the only forces taken bythis plate are those forces which would be carried thereinto throughlongitudinal movement of the hub 2i. The body member 12 takes,therefore, substantially all of the forces induced in the wrench in useand these forces are transmitted from the hub into the body member 12through the interengaging flange and groove assembly hereinabovedescribed. Torsional forces applied through the socket member are takenin part by the pawl carrier 34 through the action of the lianges 38 and41 and this carrier, in addition to its coaction as a part of thetransmission means, also serves to reinforce the hub 21 in the use ofthe wrench.

It should now be seen that the Wrench of the present invention, althoughthe over-all dimension is maintained at a minimum, nevertheless iscapable of taking extremely high stresses. All high stress loadings havebeen eliminated through the inter-engaging flange and groove assembliesand the particular transmission means used to transmit the high torquecouple to the socket member.

Although it has not been heretofore mentioned, the shaft 43 can bedriven by any suitable external source of power such as an electricmotor, a pneumatic system, or even hand driven through a suitable handcrank an gear train.

There is shown in Figures 4 through 6 a modified form of the wrench ofthe present invention which diters from the earlier described embodimentprincipally in the provision of a means for increasing the torque couplein the socket member. This embodiment of the wrench comprises a headelement and a support element 7l for mounting a handle 72, the element71 being formed preferably as an integral part of the body member 73 ofthe head element 70. The body member 73 is elongated kas compared to thebody member of the previously described embodiment, but like the bodymember 12 is formed with a concavity indicated at 74, for receiving theoperative members of the wrench. A slot 75 opens into the body memberand the inner end of this slot is enlarged to form a circular opening orbore 76 extending through the transverse wall of the body member. Thebody member carries an arcuate flange 77 concentric with the opening 76,which flange is slidably mounted within an arcuate groove 78 of aslotted hub member 79 substantially identical to the hub member 21 ofthe first described embodiment of the wrench. The hub 79 is providedwith an annular tlange 81 cornplementary to an arcuate groove formed inpart by the flange 77, as clearly illustrated in Figure 6.

It will be again seen that this embodiment ofthe wrench also includesthe internested ange and groove assembly for rotatably supporting thehub 79 and for reinforcing the hub as it is rotatably driven in the useof the wrench.

The flange S1 of the hub 79 is also provided with equally spaced teethS2 which are circumferentially spaced about the entire unslottedperiphery or" the flange. In this form of the invention the teeth S2 areengaged by a pair of spring pressed pawls d3, identical to the pawls ofthe first described form of the wrench, pivotally.

mounted in a carrier 84. The carrier 84 acts through an inturned arcuateilange SS engaged in a groove 85 formed in the iiange S1 to guide andreinforce the hub 79 in the same manner as did the carrier 34. rier 84is formed with a slot opening into a circular opening identical to theslot and opening of the carrier 34 and terminates at the inner end in aspacer member S7 having a thickness substantially equal to thek depth ofThe carthe concavity 74. The lower face of this spacer member facewiselyengages the inner surface of the transverse wall of the body member '73and acts to properly mount the carrier 84 Within the head element 70.

The carrier S4 is bifurcated at its inner endA as clearly shown inFigure 5 to form a pair Vof spaced follower elements 88 adapted toengage a cam S9 formed on the one arm of a lever member 90 which ispivotally mounted intermediate its ends by a bearing assembly 91including stationary journal 92 carried by a plate 93 fixed in a recessformed in the transverse Wall of the body member 73. Although the plate93 is'held in the recess by the fastening elements shown in Figure 6,these fastening elements carry no shear loads for the plate 93 is formedwith a relatively short, high strength shear member 94 which is mountedin an aperture formed in the transverse wall of the body member '73. Itwill be seen that the member 94 will take the shear loads created by therocking movement of the member 90 as it is alternately moved to actuatethe carrier 84 to produce the lintermittent drive of the hub '79. l

The lever member 96, at the end opposite to the cam 89, is fitted with abearing member 95 identical to the bearing or follower member 49 of thepreviously described embodimentof the wrench. This bearing ele-` mentreceives a cylindrical cam'element 96 into a transverse bore of which isiitted a pin 97. The pin is ,carried by a plate 98 eccentrically mountedto the end or" a shaft 99 rotatably supported through bearing assembliesi coaxially with the handle supporting element 71. The action of thetransmission means formed by the plate 93, pin 97, cam 96 and bearing 9Sis identical to the action of the transmission means previouslydescribed and as this action should now be clearly understood, it willnot again be described.

It should now be seen that as the shaft 99 is rotated the lever element90 will be alternately swung about its pivot to arcuately move inalternate directions the carrier'r84 through the coaction of the cam 89and the follower elements 8S of the carrier. As the vcarrier 84 isarcuately moved in a clockwise direction, as viewed in Figure 5, thepawls 83 engaged with the teeth 82 drive the hub 79 in a clockwisedirection.V This rotational drive is transmitted to the hub 102 of thesocket EP3 through the engagement of the drive elements 134 of the hubwith the drive facer of the shank of a socltet to change the amount ofamplilicatio-n of the force induced into the carrier 84.

To prevent return movement of the hub 79, as the pawls 83 drag'over theteeth 82 on the return movement of the carrier S4, holding pawls 105 andV106 are provided. lawl` 105 as clearly shownV in Figure 5 is mounted tothe one wall o f the body member 73, while pawl 1tl6 is mounted to aboss 167 opstanding from the transverse wall of thebody member 73. Thecarrier 84 is formed with an elongate slot'1tl8 to provide clearance for`the boss HB7 as the carrier is arcuately moved in the-use of theWrench. Both pawls 105 and 166 are spring urged into engagement with theteeth 82 and are l operative to prevent movement of the hub in acounterclockwise direction under the frictional drag of the pawls 83 asthe carrier is moved toward its position of Figuref5.

A closure plate 109 is mounted to the body member 73,' to complete thehead element 71 of the wrench, by a plurality lof machine 'screws orsimilar fasteners 110 is adapted to be slidably moved to engage in anotch 114 formed in the hub 79 to lock the hub against rotation in aposition in which the slot of the hub is substantially aligned with theregistering slots of the body member 73, carrier S4 and the plate 109.

The notch 114, as best shown in Figure 5, gradually increases in widthfrom the outer periphery of the hub to present a radially extendingshoulder 115 which forms a stop limiting movement of the hub whenengaged with the extending end of the detent linger 113. The detentlinger 113 is longitudinally movedl in the groove through an actuator116 slidably mounted to the exterior face of the plate 1139 by afastener 117 passed through a slot 118 and anchored to the journal 93 ofthe bearing assembly 92.

The actuator 116 also carries a pin 119 which proiects through a slot121 formed in the cover plate 169 and is secured to the detent finger113 by any means desired. The slots 11S and 121 are longitudinallyaligned, as clearly shown in Figure 4, and serve as guide means for theactuator 116 as it is moved to extend the detent linger 113 intoengagement with the hub for reception in the notch 114 and engagementwith the stop shoulder 115.

If desired a small torsional spring 122 may be interconnected betweenthe actuator 11o and the fastener 117 to normally urge the actuatordownwardly, as viewed in Figure 6, to position the detent linger 113 inan inoperative position relative to the hub 79. The spring 122, however,will permit the actuator to be moved upwardly, as viewed in Figure 6, toextend the detent linger 113 for reception in the notch 114 andengagement with the stop shoulder 115.

The detent and actuator assembly just described serves, as should now beunderstood, as a means for parking the hub and socket secured thereto ina position in which the slots are substantially aligned so that thewrench can be moved laterally over a B nut or the like securing atubular member.

Although not shown some clutch release means would be provided betweenthe external power source and the shaft 99 for disengaging the shaft 99from the power source when the detent finger 113 was moved intoengagement with the stop shoulder 115. This clutch release mechanismcould be one which could be manually operated at the time the user ofthewrench actuated the detent finger 113 to park the hub in the positionabove described.

Obviously if a closed end wrench of the general type shown in mycto-pending application Ser. No. 313,727, was desired, there would be noneed for any parking mechanism such as just described. VThis is so forin such wrenches no` slots would be provided in the housing and hubmember as in the illustrated embodiment of the present invention. Y Y

it should be further understood that the present invention may also beembodied in a closed end wrench in which no replaceable nut engagingsocket was necessary, for it would be possible to form the hub itseltwith a hex opening for receiving the nut orother member to beV turned.It is possible to convert each of the embodiments of the wrench hereinillustrated into a box or Closed end wrench by merely removing the hub,after the pawl carrier has been lifted from the recess, and substitutinga hub peripherally formed with ratchet teeth and in which there isformed a bore hexagonal in cross section.

As the pawl carrier and hubrare each removable from the recess by merelylifting the same upwardly, the` op-Y f eration of interchanging hubs isa relatively simple yone aad requires no tools other than a screw driverfor removing the fastening elements holding the cover plat to thehousing Although the now preferred embodiments of the present inventionhave been shown and described herein, it is to be understood that theinvention is not to be limited thereto, for it is susceptible to changesin form and detail within the scope of the appended claims;

I claim:

l. A wrench of the type described, comprising: a head having a workreceiving opening; a socket retaining mem-Y ber; support means formounting said member on said? head for rotative movement; means forreplaceably mounting a nut engaging socket to said member for rotativemovement therewith; an annular series of ratchet teeth formed on saidmember; a pair of pawls; a carrier mem# ber at least partiallycircumscribing said member and engaged therewith thereby to reinforcesaid'. member,

said carrier member being mounted Vfor oscillatory move-Y ment on saidhead in an arcuate path concentric with said annular series of ratchetteeth; means for pivotally mounting said pawls to said carrier forengagement with said ratchet teeth; a shaft rotatably supported by saidhead and g adapted to bedriven from an external power source; andtransmission means operatively interconnecting said shaft and saidcarrier member for arcuately driving the latter in alternate directionsas said shaft is rotatably driven to cause said pawls engaged with saidratchet Vteeth to intermittently rotate said socket retaining member andthe socket mounted thereto.

2. A wrench of the type described,rcomprising: ahead;

a hub; means carried by said hub and interengaging with means on saidhead for supporting said hub on said head' for rotative movement; anannular series of ratchet teeth formed on said hub; pawl means; a pawlcarrier; means partially carried by said head and partially carried bysaid hub coacting with means on said carrier for mounting the. latterfor oscillatory movement in a path concentric with said annular seriesof ratchet teeth, said mounting means coacting with said interengagingmeans to reinforce said A hub during rotationthereof; means forpivotally mounting said pawl means to said carrier; resilient meansholdconnected to a power source for rotating said cam whereby saidcarrier is arcuately moved in alternate directions l to cause said pawlmeans, engaged with said ratchet teeth, 1

to rotatably drive said hub.

v 3. A wrench of the type described, comprising: `a

head; a socket retaining member; support means for mounting said memberon said head for rotative movement; means for replaceably'mounting a nutengaging Y.

socket to said member for rotative movement therewith; an annular seriesof ratchet teeth formed on said n member; a pair of pawls; a carriermember means mounting said carrier member on said retaining member foroscillatory movement relative to said head in an arcuatel pathconcentric with saidannular series of ratchet teeth,

said mounting means including interttting flange and groove meansmutually reinforcing said retaining inember; means for pivotallyYrnountingsaid pawls to said carrier for engagement with said ratchetteeth; transs a mission means operatively connected to said carriermember for arcuately driving the same iny alternate directions to causesaidpawls engaged with said ratchet teeth as said carrier member isdriven in one of said alternate directions to rotatably drive saidsocket retaining memberV and the socket mounted thereto;` andpawl meanscarried by said housing and engageablewith said teeth fork holding saidsocket retaining member against movement' as said carrier member isdriven in the other of said alternate directions.

4. A wrench of the type described, comprising: a head; a hub; meanscarried by said hub and interengagng with means of said head formounting and supporting said hub on said head for rotative movement; anannular series of ratchet teeth formed on said hub; a pair of pawlmeans; a pawl carrier element; means for mounting said element forarcuate movement on said hub in a path concentric with said annularseries of ratchet teeth; means for pivotally mounting said pawl means tosaid carrier element; resilient means holding said pawl means inengagement with said ratchet teeth; cam follower means spacedly carriedby said element; an eccentric rotary cam mounted on said head andengaging said follower means; and means, including shaft means adaptedto be rotatably driven from an external power source, for rotating saidcam whereby said carrier element is arcuately driven to cause said pawlmeans, engaged with the ratchet teeth, to rotatably drive said hub.

5. A wrench, comprising: a housing having a workreceiving opening; a hubelement having concentric grooves on opposite faces thereof; flangemeans carried by said housing and received within one of said groovesfor mounting said hub to said housing for rotative movement; meansforming a driving connection between a replaceable nut engaging socketand said hub whereby said socket is rotatably driven with said hub; aplurality of ratchet teeth circumferentially formed about said hubconcentric with said grooves; a pawl carrier; flange means carried bysaid pawl carrier and received within the other of said grooves formounting said carrier to said hub element for arcuate movement in` apath substantially concentric with said ratchet teeth; a pair of pawlmeans carried by said pawl carrier spaced circumferentially of said huband engageable with said teeth; and means, including means adapted to beconnected to an external power source, for positively driving said pawlcarrier in alternate directions for intermittently engaging said pawlmeans with said teeth to drive said hub and the socket mounted thereto.

6. A wrench, comprising: a housing having internal wall means presentinga recess, with the one wail means thereof formed with a circularopening; a hub element mounted for rotation in said recess coaxiallywith said opening; ange means coaxially carried by said hub and havingconcentric grooves at opposite sides thereof; arcuate ange meansextending about said opening and slidably received within one of saidgrooves for guiding rotational movement or said hub; a plurality ofratchet teeth circumferentially formed about said iiange meansconcentric with said grooves; a pair of pawls; a pawl carrier; ilangemeans carried by said pawl carrier and slidably received within theother of said grooves for mounting said carrier within said recess forarcuate movement in a path concentric with said ratchet teeth; meansmounting said pawls to said carrier for engagement with said ratchetteeth; a rotary cam mounted eccentrically within said recess; spacedfollower means formed on said carrier and engaged with said cam onopposite sides thereof: and means for rotating said cam to alternatelyurge said followers in opposite directions whereby said carrier isarcuately moved in alternate directions to cause said pawls engaged withthe ratchet teeth to intermittently drive said hub element and the nutengaging socket mounted thereto.

7. A wrench, comprising: a housing formed with a circular opening; a hubelement mounted for rotation on said housing coaxially with saidcircular opening; a circular coaxial ange carried by said hub andpresenting concentric grooves at opposite sides thereof; ange meanscarried by said housing extending about said circular opening andslidably received within one of said grooves for guiding rotationalmovement of said hub; a plurality of ratchet teeth circumferentiallyformed on said coaxial flange; a pair of pawls; a pawl carrier; iiangemeans carried by said pawl carrier and slidably received in the other ofsaid grooves for mounting said carrier to said hub element for arcuatemovement in a path concentric with said ratchet teeth; means forpivotally mounting said pawls to said carrier for engagement with saidratchet teeth; and transmission means for driving said carrier inalternate directions including a rotor mounted eccentrically within saidrecess and engaged betweeny spaced follower means formed on said carrierwhereby rotation of said rotor-arcuately moves said carrier in alternatedirections to cause said pawls engaged with the ratchet teeth tointermittently drive said hub element and the nut engaging socketmounted thereto.

' 8. A wrench, comprising: a housing having internal wall meanspresenting a recess, with the one wall means thereof formed with aycircular opening; a hub element mounted for rotation in said recesscoaxially with said circular opening; a circularA coaxial flange carriedby said hub element and presenting concentric grooves at opposite sidesthereof; ilange means carried by said wall means arcuately extendingabout said circular opening and slidably received within onev of saidgrooves for guiding movement of said hub element during rotation of thesame; a plurality of ratchet teeth circumferentially formed on saidcoaxial flange concentric with said grooves; a pair of pawls; a pawlcarrier; iiange means carried by said pawl carrier and slidably receivedwithin theother or" said grooves for mounting said carrier for arcuatemovement in a path concentric with said ratchet teeth; means forpivotally mounting said pawls to said carrier for engagement with saidratchet teeth; an eccentric rotary cam mounted within said recess;spaced follower means formed on said carrier and engaged with said cam;means for rotating said cam whereby said carrier is arcuately moved inalternate directions to cause said pawls engaged with the ratchet teethto intermittently drive said hub element and the nut engaging socketmounted thereto; and means fixed to, said housing for closing saidrecess and engaged with said pawl carrier for holding the flange meansthereof in said one groove and for holding said hub element againstmovement disengaging the flange means of said housing from the other ofsaid grooves. i

9. A wrench of the type described, comprising: a head having an openingtherethrough; a `hub element; guide means carried by said hubelement andcoacting with guide means formed internally of said head for mountingand supporting said hub element on said headV for rotative movement; anannular series ofV ratchet teeth circumferentially formed about saidhub; a carrier member; means coaxially formed on said hub elementandinterengaging with means coaxially formed on said carrier member forVmounting and supporting said carrier member within said housing forarcuate movement in a path substantially concentric with said ratchetteeth; at least one pawl pivotally carried by said carrier member andspring biased into engagement with said teeth; means, including meansfor arcuately moving said carrier member in alternate directions, forintermittently yengaging said pawl with said ratchet teeth as saidcarrierA member is moved in one direction to intermittently drive saidhub element; and at least one pawl pivotally mounted within said headand spring biased into engagement with said ratchet teeth yfor holdingsaid hub element against rotation as said carrier member is moved in theother direction.

l0. A wrench of'the type described, comprising: a heady havingfanopening therethrough; a hub element; guide Vmeans carried by said hubelement andk coacting with guide means formed internally of said headfor mounting and supporting said hub element on said head for rotativemovement; an annular series of ratchet teeth circumferentially formedabout said hub; a carrier member; means coaxiallyformed on said hubelement and interengaging with means coaxially formed on said carriermember for mounting and supporting said carrier member within saidhousing for arcuate movement in a path substantially concentric withsaid ratchet teeth, the last named interengaging means coacting withsaid guide means for reinforcing said hub element in all rotativepositions thereof relative to said head; at least one pawl pivotallycarried by said carrier member and spring biased into engagement withsaid teeth; earn follower means formed on said carrier member', aneccentric rotary cam mounted on said head and engaging said followermeans; means including shaft means adapted to be rotatably driven froman external power source, for rotating said cam whereby said carriermember is arcuately moved in opposite directions to cause said pawl tointermittently drive said hub element as said carrier member is moved inone Cit direction; and at least one pawl pivotally mounted within saidhead and spring biased into engagement with said ratchet teeth forholding said hub element against rotation as said carrier member ismoved inthe other direction."

References Cited in thele of this patent UNITED STATES PATENTS 1,422,121Millen July' ,11, 1922 1,730,811 Erikson Oct. 8, 1929i 2,264,012 WassonNov. 25, 1941v 2,376,575 Cronan May 22, 1945 V2,529,476 Albertson Nov.14, 1950 2,578,686 Fish Dec. 18, 1951 ,n 1 2,578,687 Fish '.--s Dec. 18,1951 Y 2,600,177

Able et al. June 10,V 1952

